Water softening systems are used to remove minerals such as calcium and magnesium ions from “hard” groundwater that has dissolved these minerals from the earth. These systems often utilize a resin tank containing a resin material, such as polystyrene beads, that is initially ionically bonded to sodium ions. When the hard water flows through the resin material, the “hard” calcium and magnesium ions replace the sodium and ionically bond to the resin material due to their relatively stronger ionic charge. These systems require the periodic replenishing of sodium ions, typically though the use of a regeneration cycle where a brine solution having a high concentration of sodium salt is used to replace the calcium and magnesium ions on the resin material, thus allowing the resin material to again soften additional hard water. These water softening systems require systems to allow various types of water flow, for example a “service” flow where hard water from a ground water source is routed through the resin tank and then the softened water is routed into the household or building internal plumbing system. The systems may also utilize a flow to allow the creation of brine by filling a brine tank with a controlled amount of water, a flow to draw the brine solution into the resin tank, a flow to slowly drive the brine through the resin bed in the resin tank, a flow or flows to flush any remaining brine solution out of the resin tank at the end of the regeneration cycle, a reverse flow through the resin bed to remove any debris or sediment, and the like.
Water softening systems generally stay in the “service” flow position as this is the most commonly used operation mode of the system, and only change to the other flow positions when needed. Thus, a number of systems have been developed to control the flow of water by moving the components of the system and determining when the system is in the “home” or service orientation, and when the components of the system have been configured to be in another flow position.
In some water softening systems, two slots and switches are used to control the flow of water in the system. For example, in some systems a rotating cam simultaneously engages two mechanical switches. One of the switches solely indicates whether the system is “home” or “not home,” where “home” means the system is in the “service” flow position. A second switch indicates that the system is or is not in a regeneration position. In such systems, however, one regeneration position cannot be distinguished from any other except counting from the home switch down every other switch operation and then determining what each particular switch operation indicates. Therefore, after any memory loss event, the system must recalibrate to “home,” and thus requires inefficient movement of the cam, regardless of its relative position.
Other systems utilize a rotating cam with a series of cylindrical features, each of which engages a mechanical switch. Each cylindrical feature has high and low portions on its circumference, causing the switch to be either “closed” or “open.” The combination of switch open/closed signals provides a digital code for each position. These positions, however, are not very accurate as the initial moment any switch moves the system determines it has changed state and is in the subsequent position, meaning the entire zone of possible motion until the next change of switch state has the same digital code. Thus, after any memory loss event these systems may not accurately reflect the actual position of the system components.
Other systems utilize rotary discs with a series of uniformly placed slots that rotate through an optical sensor that detects light passing through the rotating disc. One slot is larger than the rest to indicate the “home” position, and all other regeneration positions are identified by counting the number of slots detected after the home position. These systems, however, require recalibration every time the components need to change orientations by detecting the calibration reference, i.e. the “home” slot, because the “home” position cannot be determined with certainty except by movement of the disc. Thus, each regeneration cycle has to start by moving the disc back to the starting position to confirm it to be the “home” position. Only then can the system rotate the disc and subsequently detect and count all the subsequent slots to determine the position of the disc, and when it has rotated to a desired position. This requires inefficient rotation and adds time to the procedure since the system must check for home before initiating the procedure. Moreover, the speed of the rotation in these systems may vary, particularly when the system uses a DC motor, as is typical, and the system therefore may not properly detect or interpret all the slots, as the slot width is determined by the time it takes to traverse the optical sensor. For example, if the speed is too fast the system may not detect a slot, or if it is too slow may misinterpret another slot as the “home” position.
To alleviate these possible inefficiencies, it may be desirable to provide systems, apparatuses, and methods that overcome one or more of the aforementioned drawbacks.